66 



that it is proposed to raise the exploitable size to 2 feet diamater. We will assama 

 that the average production of the soil per acre is 63 cabin feet a year, and that the 

 tree of 2 feet contains 136 cubic feet, as compare! with 85 cubic feet in the 1| feet 

 tree. The number of trees that could be felled annually would be iWx 1,600=747. 

 It might be argued that it would be better to fell 1,181 trees a year than only 747. 

 This depends on the purpose for wh,icb the trees are required and on the price realised. 

 Thus, if, owing to the better wood or less losj in oouversion, the net price realissd 

 per cubic foot for trees of the larger size were 4 annas, as compared with 3 annas for 

 the smaller trees, each of the larger treas wo.ild be worth B34, as compared with B16 

 for the smaller ; and the annual revenues woald be B25,39S or fil8,944. 



Indian forestry is not rips for elaborate calculations, and mast be satisfied with 

 felling when the revenue will be highest or the produce the most useful ; othsririse it 

 would also be necessary to consider the greater capital involved in produoing the larger 

 size timber in view to taking account of the rate of interest on thit capital. 



The correct calculation of the exploitable size is of the 

 greatest importance and demands a good deal of careful 

 local enquiry and comparison as to selling rates, etc. In 

 European countries, where forestry in all its branches has 

 long been practised, and where the wood trade is fully devel- 

 oped and established, the most profitable size is well known 

 fop each class of produce and each kind of treatment ; but 

 this is not the case in India. 



The following is an example of the sorb of calculation that would be made to 

 ascertain the most profitable size for felling for fuel : — 



It is evident from this that, assnmini; the av^raga annual increment to remain 

 fairly constant, t'lere is every financial advantage in growing trees thit will furnish 

 billets of from 10" toiC in diameter. 



The size having been decided, it only remains to deter- 

 mine the age at which the trees attain that size. This is 

 often exceedingly difficult in ladia, owing to the ring mark- 

 ing being indistinct, and also to the fact that several spesies 

 form more than one concentric ring of wood each year. In 

 such cases the rate of growth can only be determined when 

 trees of known age are to be found, or from data obtained 



